PMR writer device with multi-level tapered write pole

ABSTRACT

A perpendicular magnetic recording (PMR) head is fabricated with a multi-level tapered write pole. The write pole comprises a main pole with a tapered tip on which is formed at least one yoke that has a tapered edge. The edge of the yoke is recessed from the ABS of the tapered tip, giving the write pole a stepped profile. The tapered tip can be two sloped surfaces that are symmetric about a mid plane of the main pole or the taper can be a single sloped edge on the leading side or the trailing side of the pole. The yoke structure can consist of a single yoke formed on one side of the main pole or it can consist of two yokes formed symmetrically on both the leading and trailing sides of the main pole. Other yoke/pole combinations are also described as are various shield formations. The write pole structure creates an efficient channeling of magnetic flux to the ABS surface of the pole tip which produces magnetic recording field at high area densities.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to magnetic recording heads,particularly to perpendicular recording heads that produce recordingmagnetic fields that are substantially perpendicular to the recordingmedium. More specifically, the invention relates to a tapered shape of amagnetic pole of a recording head that allows a more efficient deliveryof a magnetic recording field to a recording medium.

2. Description of the Related Art

The increasing need for high recording area densities (up to 500 Gb/in²)is making the perpendicular magnetic recording head (PMR head) areplacement of choice for the longitudinal magnetic recording head (LMRhead).

By means of fringing magnetic fields that extend between two emergingpole pieces, longitudinal recording heads form small magnetic domainswithin the surface plane of the magnetic medium (hard disk). As recordedarea densities increase, these domains must correspondingly decrease insize, eventually permitting destabilizing thermal effects to becomestronger than the magnetic interactions that tend to stabilize thedomain formations. This occurrence is the so-called superparamagneticlimit.

Recording media that accept perpendicular magnetic recording, allowdomain structures within a magnetic layer to be formed with aperpendicular orientation relative to the disk surface, while a softmagnetic underlayer (SUL) formed beneath the magnetic layer acts as astabilizing influence on these perpendicular domain structures and alsoserves to channel a return flux back to the head to strengthen therecording field. Thus, a magnetic recording head that produces a fieldcapable of forming domains perpendicular to a disk surface, when used inconjunction with such perpendicular recording media, is able to producea stable recording with a much higher area density than is possibleusing standard longitudinal recording.

Although the magnetic media used in conjunction with perpendicularwriting are capable of storing a high area density, the write headitself must be able to produce magnetic fields of sufficient intensityand definition to make use of the media's capabilities. One approach tomatching the writer capabilities to those of the media is to fabricate atapered magnetic pole tip. Such a design presents a smaller footprintwhere it emerges at the ABS, yet delivers more flux. U.S. Pat. No.7,322,095 and U.S. Patent Applications 2008/0112082 and 2005/0237665(Guan et al.) show such a main pole tapered preferably at its trailingedge and shielded on four sides.

Traditionally, a top yoke (TY), a bottom yoke (BY) or both have beenused in PMR writers to deliver flux to the main pole. As a consequence,these yokes are often referred to as auxiliary poles. Referring to FIGS.1 a-1 b, there are shown the following prior art arrangements.

FIG. 1 a shows a highly schematic diagram of a side view of a PMR singlepole (14) writer positioned above a moving magnetic media (16). Themedia is moving in the direction of the arrow (180). The term “leadingedge” (indicated in the figure by the legend “Leading Edge”) of thewriter or its various elements refers to the edge or surface into whichthe disk is moving. Typically, the read head, which is not shown here,would be formed on the leading edge side of the writer, so an area onthe disk moves past the reader before passing beneath the writer. Wherea figure does not indicate a disk or a reader, the notation of leadingor trailing will be indicated by a legend. For consistency ofdescription, a set of x, y, z axes define directions in this andremaining figures that display a PMR writer. The positive y-direction isaway from the ABS of the writer. The x-direction defines the thicknessdirection of the pole layer (14) and the yoke layer (17) (i.e. thedirection of layer formation by plating or the like). The positivez-direction (circle with a central dot) is out of the figure plane.

The main pole of this writer (14) consists of flared portion (11), whichwill be more clearly shown in FIG. 1 b, and a narrow pole tip (13),which extends from the flared portion and presents an exposed ABS shape(19) just above the media (16). The writer has a return pole (15), thatcompletes a magnetic flux loop (not shown), out from the main pole,through the media soft underlayer, back up through the return pole (15)and around through a bottom yoke (17) (formed beneath the pole) to whichthe pole tip is attached. A single exemplary current carrying coilwinding (12) is shown as wrapped around the yoke (17) and represents themechanism by which a magnetic field is generated. The ABS surface of thewriter is indicated by the dashed line with the legend “ABS”. The mainpole (14), in this configuration, is mounted on the leading edge surfaceof the bottom yoke (17).

Referring next to FIG. 1 b there is shown, schematically, a top view ofthe main pole (14) and pole tip (13), as it would appear if viewed alongthe thickness direction of the writer, or the arrow (180), or the x-axisof FIG. 1 a. Note, as discussed above, that the main pole (14) generallyhas a horizontal shape that includes a small rectangular portion (13)and a triangular flaring portion (11). The pole tip projects from thenarrow portion of (1). The ABS surface (19) of the pole tip (13) has awidth, w, and the pole tip itself has neck height NH, defined by itslength before the taper if the pole tip is reached.

Referring now to FIGS. 2 a, 2 b and 2 c, there are shown three possibleapproaches to channeling magnetic flux from a yoke to a main pole, anyof which could be applied to the configuration of FIG. 1 a. In FIG. 2 a,there is schematically shown the main pole (14) attached beneath theyoke (17 a), which thereby acts as a top yoke. Typically, the distance,d, between the perpendicular edge of the yoke (18 a) and the tip of thepole (19) is approximately 1.5 microns or greater.

In FIG. 2 b, there is schematically shown the same main pole (14), withthe yoke (17 b) now serving as a bottom yoke and the same approximate1.5 micron or greater distance between the yoke edge (18 b) and the poletip.

In FIG. 2 c, there is shown a main pole configuration in which the mainpole is sandwiched between a top (17 a) and bottom (17 b) yoke.

Referring finally to FIG. 2 d, there is shown a top view of theconfiguration in FIG. 2 c, in which the main pole (14) is shownprojecting from between the top and bottom yokes (17 a)/(17 b). Note,this figure would appear substantially the same if it were used toillustrate the configurations of FIG. 2 a or 2 b, the difference beingthat only one yoke (17 a) or (17 b) would be seen.

Along with the above cited methods of attaching a pole tip to a topyoke, a bottom yoke or both, the tip itself may be provided with atapering profile just above its emergence at the ABS of the writer.Referring to FIGS. 3 a, 3 b and 3 c, there are shown three pole tipswith trailing edge, leading edge and both leading and trailing edge,tapers. Note that a trailing (leading) taper refers to a bevel(reduction in thickness) that begins at the trailing (leading) edge faceof the pole tip, a distance away from the ABS (shown as a dashed line)and produces a diminishing thickness towards the ABS face of the poletip, at which point the bevel stops.

The methods by which the pole tip is tapered and the general design ofthe taper are also taught in the following patents and publishedapplications.

U.S. Patent Application 2005/0219743 (Guan et al—Headway) discloses thatthe main pole may be tapered at the leading or the trailing edge.

U.S. Pat. No. 7,133,252 (Takano et al) shows that the main pole may betapered at the leading edge or the trailing edge or both.

U.S. Pat. No. 5,600,519 (Heim et al) discloses a tapered pole tip.

U.S. Patent Application 2008/0316653 (Sasaki et al). FIG. 12 shows thepole tapered and the nonmagnetic layer 17 also tapered.

SUMMARY OF THE INVENTION

A first object of this invention is to provide a pole structure for aperpendicular magnetic recording (PMR) writer capable of recording athigh area densities.

A second object of the present invention is to provide such a polestructure for a perpendicular magnetic recording head in which the writemagnetic field is increased by means of more efficient provision ofmagnetic flux to the ABS of the pole tip.

A third object of the present invention is to provide a PMR writer withenhanced writing capabilities at narrow track widths.

A fourth object of the present invention is to provide a PMR writer withimproved field gradient and other performance enhancements provided byimproved writing capabilities.

A fifth object of the present invention is to provide such a PMR writerwith a shielded pole structure so that writing to adjacent tracks iseliminated.

The objects of the present invention are realized by the formation of awrite pole with multi-level tapering in the direction perpendicular tothe air bearing surface (ABS). The taper is applied to both the pole tip(called the 1^(st) taper) and to the edges of the yoke structures, whichcan be above or below the pole tip, to which the pole tip is attached(called the 2^(nd) taper).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a schematic representation of side view of an exemplaryprior art PMR having a single main pole.

FIG. 1 b is a schematic top view of the same PMR showing the shape ofthe main pole.

FIGS. 2 a, 2 b and 2 c are prior art schematic representations showingexemplary main poles attached to top (2 a), bottom (2 b) and top andbottom (2 c) yokes, so that the edges of the yokes are recessed from thepole tips.

FIG. 2 d is a top view of any of the configurations in FIGS. 2 a, 2 b or2 c.

FIGS. 3 a, 3 b and 3 c show three prior art pole tips with tapers attheir trailing, leading and leading and trailing sides.

FIG. 4 a is a schematic side cross-sectional illustration of anembodiment of the present invention showing a multi-level tapered mainpole.

FIG. 4 b is a top view of the configuration in FIG. 4 a.

FIG. 5 is a graphical representation showing the on-track performance ofa PMR using the double-level tapered main pole configuration of thecurrent invention as compared with a reference PMR that is shielded andhas a single level of tapering but lacks the double taperedconfiguration.

FIGS. 6 a-6 f shows six schematic illustrations of side cross-sectionalviews of possible combinations of top yokes and bottom yokes withleading and trailing tapers, to which is attached a main pole with a tiphaving trailing and/or leading tapers.

FIGS. 7 a-7 c show three schematic illustrations of side cross-sectionalviews of a main pole having trailing, leading and both leading andtrailing tapers, sandwiched between a top yoke with a leading taper anda bottom yoke having a trailing taper.

FIG. 8 shows a schematic side cross-sectional view of a three-leveltapered write pole.

FIG. 9 shows a schematic side cross-sectional view of a smalldouble-level tapered main pole, partially sandwiched (stitched) betweenan upper yoke and a lower yoke.

FIGS. 10 a-10 d shows a view of the ABS surface the pole tip of any ofthe multi-level tapered main poles of the present invention, in an (a)unshielded configuration; (b) trailing edge shielded; (c) trailing edgeand side shielded; (d) shielded on all four sides.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiment of the present invention is a multi-leveltapered write pole structure for use within a perpendicular magneticrecording (PMR) head. A first level of the tapering (i.e. an increasingthickness in the layer produced by a bevel) begins at the ABS edge ofthe pole tip (this is called the 1^(st) taper) and extends in thepositive y-direction (away from the ABS). The 1^(st) taper ends and thepole layer then retains a constant maximum thickness from that pointbackwards (i.e., away from the ABS). A second level of tapering beginsat the edges of the upper and/or lower yoke structure (2^(nd) taper)which contacts the pole tip on the constant thickness portion of eithera top surface or a bottom surface and proceeds in the positivey-direction until the yoke layer attains a constant thickness.

Referring to FIG. 4 a, there is shown a schematic drawing of a side-viewcross-section of a double-level tapered write pole that is a preferredembodiment of the present invention. In this embodiment, the main pole(14) is sandwiched between a top yoke (17 a) and a bottom yoke (17 b)that are formed conformally on the main pole on its trailing (top) andleading (bottom) surfaces respectively. The top yoke (17 a) is formed onthe top surface (trailing surface) of the main pole; the bottom yoke (17b) is formed on the bottom surface (leading surface) of the main pole.This particular configuration is reflection-symmetric about a z-ymid-plane passing through the mid-line (shown as a dashed line) of themain pole.

The taper of the main pole is defined by a region of symmetrically(about said z-y mid-plane) increasing thickness in the direction awayfrom (i.e. in the positive y-direction defined in FIG. 1 a)) the ABS endof the main pole (19). The taper terminates at a back edge (21), fromwhich edge distally backwards, the main pole remains flat and horizontaland the thickness of the pole remains constant as the pole extends awayfrom the ABS. Note, the direction away from the ABS of the pole tip maybe referred to hereinafter, with equal accuracy, as the distal directionor the positive y-direction.

As is indicated in the drawing, the vertical front edges (18 a), (18 b),of the yokes have planar faces that are parallel to the ABS of the mainpole (19) and that the second taper is formed as an upward sloping(beveled) surface extending distally from the planar edge face (18 a) tothe trailing surface of the top yoke and from the planar edge face (18b) of the bottom yoke (17 b) downward to the leading surface of thebottom yoke. Note again that the taper of the top yoke slopes upwardfrom edge (18 b) towards its trailing surface, whereas the taper of thebottom yoke (17 b) slopes downward towards its leading edge. The facesof these edges (18 a)/(18 b) are formed distally to the back edge (21)of the main pole taper and are recessed from the pole tip ABS (19) by anamount between approximately 0.3 and 1.0 microns. Thus, there is a shortexposed flat portion (23) of the top and bottom surfaces of the mainpole between the back edge of the 1^(st) taper (21) of the pole and thefront edge of the 2^(nd) taper (18 a), (18 b) of the yokes. The heightof the vertical faces of the front edges (18 a), (18 b) is betweenapproximately 0 and 0.2 microns. The increasing thickness of the secondtaper in the distal (positive y) direction stops and the yoke maintainsa substantially constant thickness thereafter. The thickness of the2^(nd) taper region is between approximately 0.3 to 1.0 microns. Thehorizontal shape of the 2^(nd) taper region is conformal to the shape ofthe flaring portion of the main pole (14), which is generally atriangular shape as shown in FIG. 4 b. The thickness of the combinedlayers is between approximately 0.5 and 3.0 microns and the materialforming the layers is alloys of Fe and Co as is known in the art.

It is to be noted that the front edges of the 2^(nd) taper on the upperand lower yokes (18 a), (18 b) are much closer to the ABS than thetop/bottom yokes of conventional PMR designs, which permits the deliveryof more flux to the ABS of the pole tip (19). In addition, the conformalshape of the 2^(nd) tapered region to the main pole itself, produces atapered front cross-sectional aspect which also helps to efficientlyconcentrate more flux to the pole tip ABS (19).

Referring to FIG. 4 b, there is shown a top schematic view of the yokeand main pole as would be seen looking towards the trailing surface ofthe top yoke. The front edge of the 2^(nd) taper (18 a) or (18 b) isshown in outline as is the back edge of the 1^(st) taper (21). Thetriangular portion of the main pole (11) is conformally covered by thetapered portion top or bottom yoke (11 a), if a single yoke is used, orby both yokes, if a sandwich configuration is constructed.

It is to be noted that fabrication of the pole structure can beunderstood with reference to FIG. 4 b as described above. Thefabrication can be easily accomplished using the masking process as forprior art designs with only slight modification of mask alignment totake into account the recessing of the yokes relative to the pole tip.In-plane alignment should not be difficult, however, because of the factthat the recessing (distance between (19) to (18 a)) is at least 0.3microns from the ABS, where 0.3 microns is the width of the pole.

More specifically, a tapered bottom yoke (17 b) can be created first bymilling (via an ion beam etch, a RIE etch or the like) a sloped regionin an AlOx substrate having a smooth planar surface, followed by platingor sputtering a yoke layer into the milled region and applying CMP toform a smooth planarized surface. After the pole (19) is formed on theplanarized bottom yoke, a tapered top yoke (17 a) can be formed on thepole by plating or sputtering a conventional (un-tapered) top yoke asdefined in the prior art and then milling the front of the yoke tocreate the necessary taper. The pole is formed, also by plating orsputtering through a mask, onto the already planarized bottom yoke.Here, the mask is aligned over the bottom yoke to create the necessaryrecess of the yoke behind the tip of the pole. Once the pole is formed,the top yoke (17 a) is formed, as noted above, on the pole, using aconventional mask that is properly aligned to create the requiredrecess. Once the top yoke is formed and tapered, the pole tip can alsobe tapered, again using milling or RIE as the mechanism

Referring to FIG. 5, there is shown a graphical comparison of themulti-level tapered main pole of the present invention as shown in FIGS.4 a and 4 b with a reference writer using a single pole tip withtrailing and leading edge tapers right at the ABS. The vertical axismeasures magnetic field H_(y) (Oe) into the magnetic medium and thehorizontal axis measures downtrack position in cm.

The reference pole has only 1^(st) level tapering and lacks the taperedand recessed top and bottom yokes shown as (17 a) and (17 b) in FIG. 4a. As shown in the graphs, the curve representing the present invention(1) shows a significant improvement in peak H_(y) by approximately 380Oe or approximately 4%. It is to be noted that the significantimprovement in field strength of the present invention might make itdesirable to further optimize shield design, so that cross-track fluxwill be reduced.

Referring now to FIGS. 6 a-6 f, there are shown six schematiccross-sectional side views of combinations of 1^(st) (pole) and 2^(nd)(yoke) tapers for a main pole (14) and an attached recessed top yoke (17a) or bottom yoke (17 b) that could meet the objects of the presentinvention. In FIG. 6 a both the 1^(st) and 2^(nd) tapers are trailingedge tapers. In FIG. 6 b, they are, respectively, leading and trailingedge tapers. In FIG. 6 c, they are, respectively, leading/trailing andtrailing edge tapers. In FIG. 6 d, they are trailing and leading edgetapers. In FIG. 6 e, they are, respectively, leading, leading edgetapers and, finally, in FIG. 6 f they are leading/trailing and leadingedge tapers.

Referring now to FIGS. 7 a-7 c, there are shown three schematiccross-sectional side views of tapered poles (14), each formed between atop (17 a) and bottom (I 7 b) tapered yoke to provide 1^(st) and 2^(nd)tapers. Either of these three configurations could meet the objects ofthe present invention. In FIG. 7 a the top yoke (17 a) has a trailingedge taper, the bottom yoke (17 b) has a leading edge taper and the mainpole (14) has a trailing edge taper. In 7 b, the top and bottom yokesare the same as in 7 a, but the main pole (14) has a leading edge taper.Finally, the configuration of FIG. 7 c has a main pole (14) with asymmetric leading/trailing edge taper.

Referring to FIG. 8, there is shown a 3-level tapered pole comprising amain pole (14) sandwiched between a first top and bottom yoke (171 a),(171 b), the entire configuration then being sandwiched between a secondtop and bottom yoke (172 a), (172 b). This 3-level tapered pole wouldalso meet the objects of the present invention and is an alternativeembodiment thereof.

Referring to FIG. 9, there is shown a stitched, 2-level main poleconfiguration in which a shortened main pole (14) is affixed between twoyokes (17 a) and (17 b). Such a stitched configuration allows theformation of a short pole segment (14) which can be advantageous in thatthe shorter segment produces stable domain structures that persistduring inactive periods when the write current is off. Such a structurewould form another embodiment of the present invention.

Referring now to FIGS. 10 a-10 d, there are shown four views of the ABSof the pole tip of the present invention in different shieldedconfigurations. FIG. 10 a shows the pole tip unshielded. FIGS. 10 b-10 dshow the pole tip surrounded respectively by a trailing shield (10 b) atrailing shield and two side shields (10 c) and a trailing shield, aleading shield and two side shields (10 d). These embodiments are meantto illustrate the fact that shielded configurations of the multi-leveltapered pole structure are possible using similar shield designtechnology of the prior art. It is to be noted, however, that thesignificantly increased flux produced by the multi-level tapered pole ofthis invention could very well require that shield dimensions bere-formulated to provide the protection against unwanted side writing atthe new levels of write field intensity. Shield structures must beformed with sufficient volume and of proper magnetic moment materials sothat they do not saturate under the influence of the strong writingfields produced by the present pole configurations. At present, however,the shield designs used in testing the present invention, such as usedin generating the graphs of FIG. 4 have proven adequate.

As is understood by a person skilled in the art, the preferredembodiment of the present invention is illustrative of the presentinvention rather than limiting of the present invention. Revisions andmodifications may be made to methods, materials, structures anddimensions employed in forming and providing a PMR head having amulti-level tapered main pole, while still forming and providing such aPMR head and pole and its method of formation in accord with the spiritand scope of the present invention as defined by the appended claims.

1. A PMR head comprising: a main pole having a top surface and a bottomsurface and having a 1^(st) taper defined by a region of increasingthickness in a positive y-direction away from an ABS edge of said mainpole, wherein said taper terminates at a back edge of said main pole andwherein said main pole has a constant thickness in said positivey-direction thereafter; at least one tapered yoke having a 2^(nd) taper,wherein said at least one tapered yoke is formed conformally on the topor bottom surface of said main pole, wherein said 2^(nd) taper isdefined by a region of increasing thickness of said yoke in saidpositive y-direction, said region of increasing thickness beginning at ayoke edge closest to said ABS edge of said main pole and increasing in adirection away from said ABS until said region of increasing thicknessbecomes a region of constant thickness thereafter; and wherein said yokeedge closest to said ABS edge of said main pole contacts said flatregion of constant thickness of said main pole and is recessed adistance from said ABS edge.
 2. The PMR head of claim 1 wherein saidrecess distance is between approximately 0.3 and 1.0 microns betweensaid ABS edge of said main pole and said yoke edge closest to said ABSedge of said main pole.
 3. The PMR head of claim 1 wherein said yokeedge closest to said ABS edge of said main pole is characterized by aface that is parallel to said ABS edge of said main pole and whereinsaid face extends perpendicularly from said main pole to a heightbetween approximately 0 and 0.2 microns.
 4. The PMR head of claim 1wherein there is a top and bottom yoke, symmetrically disposed about amid-plane of said main pole, wherein said top yoke is formed on saidtrailing edge surface of said main pole and said bottom yoke is formedon said leading surface of said main pole and wherein a 2^(nd) taper ofsaid top yoke is marked by a slope towards a trailing surface of saidyoke and wherein a 2^(nd) taper of said bottom yoke is marked by a slopetowards a leading surface of said yoke.
 5. The PMR head of claim 4wherein said main pole is symmetrically tapered about a mid-plane ofsaid main pole.
 6. The PMR head of claim 4 wherein said main pole istapered only on its trailing surface.
 7. The PMR head of claim 4 whereinsaid main pole is tapered only on its leading surface.
 8. The PMR headof claim 1 wherein there is only a top yoke and said top yoke is formedon a trailing surface of said main pole and wherein said 2^(nd) taperslopes upward towards the trailing surface of said top yoke.
 9. The PMRhead of claim 1 wherein there is only a bottom yoke and said bottom yokeis formed on a leading surface of said main pole and wherein said 2^(nd)taper slopes downward towards the leading surface of said bottom yoke.10. The PMR head of claim 8 wherein said 1^(st) taper is characterizedby an upward slope towards said trailing surface of said main pole. 11.The PMR head of claim 8 wherein said 1^(st) taper is characterized by adownward slope towards said leading surface of said main pole.
 12. ThePMR head of claim 9 wherein said 1^(st) taper is characterized by anupward slope towards said trailing surface of said main pole.
 13. ThePMR head of claim 9 wherein said 1^(st) taper is characterized by adownward slope towards said leading surface of said main pole.
 14. ThePMR head of claim 4 wherein said top yoke and said bottom yoke areformed as double layers, wherein said top yoke is a first top yoke layerhaving a 2^(nd) taper on which is formed a second top yoke layer,recessed from said first top yoke layer and having a 3^(rd) taper andwherein said bottom yoke is a first bottom yoke layer having a 2^(nd)taper on which is formed a second bottom yoke layer, recessed from saidfirst bottom yoke layer having a 3^(rd) taper and wherein said first topyoke layer is formed on said top surface of said main pole and isrecessed from said ABS of said main pole and wherein said first bottomyoke layer is formed on said bottom surface of said main pole andpositioned symmetrically to said first top yoke layer and wherein saidsecond bottom yoke layer is positioned symmetrically to said second topyoke layer.
 15. The PMR head of claim 4 wherein said top yoke and saidbottom yoke are stitched to said main pole.
 16. The PMR head of claim 4wherein said main pole, said top yoke and said bottom yoke are formed byplating or sputtering alloys of Fe and Co.
 17. The PMR head of claim 1further including a magnetic shield formed as a trailing shield, orformed as a trailing shield and two laterally disposed side shields orformed as a four sided shield having a leading shield portion, atrailing shield portion and two laterally disposed side shields andwherein said shields are formed of a material and of a size as not tosaturate with the magnetic writing field produced by the head.
 18. Amethod of forming a multi-level tapered write pole for a PMR head,comprising: providing a substrate having a planar surface; forming insaid substrate a trench, wherein a front portion of said trench isbounded by a front edge and a face extending therefrom into saidsubstrate perpendicular to said substrate surface and said trenchincludes a downward sloped region extending rearward from said face anda flat region parallel to said substrate surface extending rearwardthereafter; forming a bottom yoke in said trench, whereby said slopedregion defines a 2^(nd) taper on said bottom yoke and wherein a frontedge of said bottom yoke is defined by said front edge of said trench;planarizing said bottom yoke; forming a main pole over said planarizedbottom yoke, a front edge of said main pole extending forward beyondsaid front edge of said bottom yoke and defining an ABS of said mainpole; forming a top yoke layer on said main pole, wherein said top yokeis vertically above and horizontally coextensive with said bottom yoke;forming on said top yoke layer a sloped region substantially mirrorsymmetric with respect to said sloped region in said bottom yoke;shaping said main pole to produce thereon a 1^(st) taper; wherein said1^(st) taper ends a distance, d, before said front edge of said bottomyoke begins.
 19. The method of claim 18 wherein said trench is formed byeither milling or by an RIE etch.
 20. The method of claim 18 whereinsaid bottom yoke is formed by either sputtering or plating an alloy ofCo and Fe.
 21. The method of claim 18 wherein said main pole is formedby plating or sputtering a layer of Co and Fe alloy using a maskinglayer that is aligned on said bottom yoke.
 22. The method of claim 18wherein said top yoke is formed by plating or sputtering an alloy of Feand Co using a masking layer formed on said main pole.
 23. The method ofclaim 18 wherein said recess distance is between approximately 0.3 and1.0 microns between said ABS of said main pole and said yoke edgeclosest to said ABS edge of said main pole.
 24. The method of claim 18wherein said yoke edge closest to said ABS edge of said main pole ischaracterized by a face that is parallel to said ABS edge of said mainpole and wherein said face extends perpendicularly from said main poleto a height between approximately 0 and 0.2 microns.